Neratinib Approved by FDA for Extended Adjuvant Treatment of HER2-Positive Breast Cancer
Yesterday, the U.S. Food and Drug Administration (FDA) approved neratinib (Nerlynx) for the extended adjuvant treatment of adult patients with early-stage HER2-positive breast cancer who have previously been treated with a regimen that included trastuzumab.
This approval was based on the multicenter, randomized, double-blind ExteNET trial, which included 2,840 women with HER2-positive breast cancer. Half of these patients received neratinib within 2 years of completing adjuvant trastuzumab treatment, and the other half received placebo for 1 year.
After 2 years, invasive disease–free survival was 94.2% in patients who received neratinib, compared with 91.9% in those who received placebo (P=.008). Invasive disease–free survival was defined as the time between the randomization date to the first occurrence of invasive recurrence (local/regional, ipsilateral, or contralateral breast cancer), distant recurrence, or death from any cause, within 2 years and 28 days of follow-up.
The most common adverse reactions (> 5%) were diarrhea; nausea; abdominal pain; fatigue; vomiting; rash; stomatitis; decreased appetite; muscle spasms; dyspepsia; aspartate transaminase or alanine transaminse increase; nail disorder; dry skin; abdominal distention; weight loss; and urinary tract infection. The most common adverse reaction leading to discontinuation of treatment was diarrhea, observed in 16.8% of neratinib-treated patients. Hepatotoxicity or increases in liver transaminases led to drug discontinuation in 1.7% of neratinib-treated patients.
The recommended dose of neratinib is 240 mg (6 tablets) given orally once daily with food, continuously for 1 year. Antidiarrheal prophylaxis should be initiated with the first neratinib dose and continued during the first 2 cycles (56 days) of treatment and as needed thereafter.